We report on a study of the ratio of inclusive three-jet to inclusive two-jet production cross sections as a function of total transverse energy in $p\overline{p}$ collisions at a center-of-mass energy $\sqrt{s}\phantom{\rule{0ex}{0ex}}=\phantom{\rule{0ex}{0ex}}1.8$ TeV, using data collected with the D0 detector during the 1992--1993 run of the Fermilab Tevatron Collider. The measurements are used to deduce preferred renormalization scales in perturbative $O({\ensuremath{\alpha}}_{s}^{3})$ QCD calculations in modeling soft-jet emission.